Canon EOS 7D Mark II Basic Instruction Manual page 77

AF Operation Indicator
AF Points Lighting Up in Red
The AF points light up in red in low-light conditions.
AF-Assist Beam with the Built-in Flash
Under low-light conditions, when you press the shutter button halfway,
the built-in flash may fire a brief burst of flashes. It illuminates the
subject to help autofocusing.
f: Selecting the AF OperationN
When you press the shutter button
halfway and the camera is focusing with
AF, the <i> icon will appear on the
lower right of the viewfinder.
In the One-Shot AF mode, the icon also
appears if you press the shutter button
halfway after focus is achieved.
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